模拟自然污秽绝缘子串的电压分布试验研究

输电线路绝缘子串电压分布受多种因素的影响,选用江西省典型污秽区110 kV在线运行XWP2–70绝缘子串作为试品,根据自然污秽的现场污秽度及分布规律,设计了5类不同污秽度的污秽绝缘子试验,并采用小球间隙法研究绝缘子串的电压分布。试验结果表明:洁净的绝缘子串电压分布主要受电容影响;污秽条件下绝缘子表面结构组成发生变化,绝缘电阻降低;在不同染污方式及污秽度的情况下,绝缘子串电压分布受电容、绝缘子表面干区和剩余污层及绝缘电阻的共同影响。该研究为改善绝缘子串的电压分布提供了指导依据。

Test Study on Voltage Distribution of Simulated Natural Contamination Insulator Strings

Voltage distribution of transmission line insulator strings is affected by insulator surface pollution distribution,insulator capacitance itself and stray capacitance distribution.110 kV online operation XWP2-70 insulator strings in typical pollution areas in Jiangxi Province were selected to analysis the voltage distribution of a polluted insulator string.According to the insulator string’s composition and distribution of natural pollution,five different degrees of artificial pollution tests were designed to study the voltage distribution by the ball gap discharging method.In the natural pollution state,the uneven distribution of the voltage of the online insulator leads to the lower flashover voltage.The test results show that the voltage distribution of the clean insulator is affected mainly by its distribution of capacitance.But in the pollution state,the surface composition of the insulator is changed and its insulation resistance is getting smaller.Under the different types and degrees of pollution,the voltage distribution of the insulator is affected not only by its capacitance distribution,but also by its dry areas’ distribution of surface and its remaining pollution layer and insulation resistance.